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chapter 8

Augmented reality

and

computer supported cooperative

work

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Augmented reality

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Augmented realityAR is a combination of :

a real scene viewed by a user and,

a virtual scene generated by a computer that augments the scene

with additional information.

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Augmented realityAugmented Reality vs. Virtual RealityAugmented

RealitySystem augments the

real world sceneUser maintains a

sense of presence in real world

Needs a mechanism to combine virtual and real worlds

Hard to register real and virtual

Virtual RealityTotally immersive

environmentSenses are under

control of systemNeed a mechanism

to feed virtual world to user

Hard to make VR world interesting

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Augmented realityExamples

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Augmented realityExamples

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Augmented realityExamples

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Augmented realityExamples

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Augmented reality

Display Technologies

Monitor Based Display:LaptopsCell phonesProjectors

Head Mounted Display:Video see-throughOptical see-through

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Augmented reality Monitor Based Augmented Reality

•Simplest available

•Treat laptop/PDA/cell phone as a window through

which you can see AR world.

•Sunglasses demo

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Augmented reality

Successful commercialization:

Yellow line in football broadcasts

Glowing hockey puck

Replace times square billboards with own commercials

during New Year’s Eve broadcasts

Baseball cards

Ad campaigns

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Augmented reality

Advantage of Monitor Displays

Consumer-level equipment

Most practical

A lot of current research aimed here

Other current active area is a flip-down optical

display.

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Augmented reality Video see-through HMD

•Works by combining a closed-view HMD with one or two

head-mounted video cameras

•Video cameras provide the user’s view of the real world.

•Video from cameras is combined with graphics images

by the scene generator to blend the two worlds.

•Result is sent to the monitors from the user’s eyes to

the closed-view HMD.

•User has no direct view of the real world.

•If power is off, the user is “blind.”

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Augmented reality Video see-through HMD

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Augmented reality Advantage of Video see-through HMD

Flexibility in composition strategies

Video see-through is much more flexible about how it merges real and

virtual - they are both in digitized form so compositors can do a pixel-

by-pixel comparison.

Produces more compelling environments.

Real and Virtual delays can be matched

Delay the video of the real world to match the delay in the virtual image

stream.

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Augmented reality Optical see-through HMD

•Works by placing optical combiners in front of the user’s eyes.

•Combiners are partially transmissive - so user can look directly

through them and see the real world.

•Combiners are partially reflective - so user can also see virtual

images bounced off the combiners from head-mounted monitors.

•Can see through the display even if the power is turned off.

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Augmented reality Optical see-through HMD

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Augmented reality Advantage of optical see-through HMD

Simplicity

Resolution

Optical limits the virtual resolution to the resolution of the display devices but

not the user’s view of the real world.

No Eye Offset

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computer supported cooperative

work

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Computer supported cooperative workWhat is CSCW?

•CSCW (Computer-Supported Cooperative Work) refers to the field of

study which examines the design, adoption, and use of groupware.

•Despite the name, this field of study is not restricted to issues of

"cooperation" or "work" but also examines competition, socialization, and

play.

•The field typically attracts those interested in software design and social

and organizational behaviour, including business people, computer

scientists, organizational psychologists, communications researchers, and

anthropologists, among other specialties.

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Computer supported cooperative workWhat is groupware?

•Groupware is technology designed to facilitate the work of groups.

•This technology may be used to communicate, cooperate, coordinate,

solve problems, compete, or negotiate.

•While traditional technologies like the telephone qualify as groupware,

the term is ordinarily used to refer to a specific class of technologies

relying on modern computer networks, such as email, newsgroups,

videophones, or chat.

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Computer supported cooperative workWhy is groupware worth paying attention to in the first place?

Groupware offers significant advantages over single-user systems. These

are some of the most common reasons people want to use groupware:

To facilitate communication: make it faster, clearer, more persuasive

To enable communication where it wouldn't otherwise be possible

To enable telecommuting and to cut down on travel costs

To bring together multiple perspectives and expertise

To form groups with common interests where it wouldn't be possible to gather a

sufficient number of people face-to-face

To save time and cost in coordinating group work

To facilitate group problem-solving

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Computer supported cooperative workWhy is groupware worth paying attention to in the first place?

Groupware technologies are typically categorized along two primary

dimensions:

Whether users of the groupware are working together at the same

time ("realtime" or "synchronous" groupware) or different times

("asynchronous" groupware), and

Whether users are working together in the same place ("colocated"

or "face-to-face") or in different places ("non-colocated" or "distance").

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Computer supported cooperative work

Blackboarding

VotingPresentation

support

Shared computers

Videoconferencing

Chat rooms

EmailNewsgroups

Time

Same(synchronous)

Different(asynchronous)

Place

Same(colocated)

Different(distance)

Most work involves all of these modalities

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Computer supported cooperative workIssues in the Groupware Design Process

• Organizing and scheduling for groups is more difficult than for

individuals.

• Group interaction style is hard to select for beforehand, whereas

individual characteristics are often possible to determine before a

study is conducted.

• Pre-established groups vary in interaction style, and the length of time

they've been a group affects their communication patterns.

• New groups change quickly during the group formation process.

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Computer supported cooperative workIssues in the Groupware Design Process

• Groups are dynamic, roles change.

• Many studies need to be long-term, especially when studying

asynchronous groupware.

• Modifying prototypes can be technically difficult because of the added

complexity of groupware over single-user software.

• In software for large organizations, testing new prototypes can be

difficult or impossible because of the disruption caused by introducing

new versions into an organization.